> and generating about 2500 interrupts for the usb controller per 10> seconds and when i finally break it off and give it "sync" it uses> about two minutes with about 4500 per 10 seconds to get it all on> disk. On 2.4 the machine becomes more and more sluggish if I let it> go more than a short minute.

I had the same problem with USB 1.1. I solved it by writing aLD_PRELOAD-able shared library which overrides write() to do afdatasync() on the filehandle after a megabyte worth of writes.